Digesting apparatus



HID. RANKIN. DIGESTING APPARATUS. APPLICATION FILED JUNE 26,1918.

Patented Jan. 4, 1921.

INVENTORH M0. RANK/N.

ATTORNEY;

um'reo STATES PATENT ormcs,

nine! n. Remus, or OAKLAND, oetirozemn, Assxonos or seven-owns 'ro ,LOUIS sLoss, or SAN FRANCISGU, entire-sum.

PIGESTING APPARATUS.

' mg, dissolving, internally rearranging or rendering them soluble.

An object. of the invention is to provide an apparatus-for subjecting a mixture of liquid and material" to high temperatures in a closed vessel.

I ing' withdrawn ,Another object ofthe invention is to pro vide means for controlling the pressure of the gases and vapors in the vessel without Wasting the g ses and vapors.

A; further obgect of the invention is to provide an apparatus for reducing the pressure of the gases and vapors when the pressure becomes excessive by- Withdrawing gesesend vcporand subsequently introducpressure falls.

The invention possesses other solvents: geous features, some of which, witlrthe fcregoing, will he set forth at length in the following description, where I shall outline U the excess vapor chambers may be such inde, pendently connected to the vessel and in in full, that form of the invention which I have selected -for illustration in the drawing accompanying and forming part of the present specification. In said-drawing I have shown only one form-of my invention, but

it is to be understood that I do not limit my self to such form since the invention, as expressed in the claims, may be embodied in a plurality of forms. Y

, The drawing is a vertical section of e digesting apparatus embodying my inven; tion.

I Certain materials or substances are rebellious to chemical changes, even when treatedwith acids, but processes of treating such materials or substances to decompose,-

rearrange or render them soluble, have been developed and these processes involve the subjection of the material or substance in a closed vessel to the action of acid at a temperature uol to or in excess of the boiling int of t eacid This produces a very igh pressure within the vessel, which is not essential to the desired reaction, rendering Specification of letters Patent.

gases and vapors when the:

- the vessel.

Patented J an. 4:, 1921.

Application filed June 26, 1918. Serial so. 242,121,.

it necessary to construct the vessel of great cturel strength and rendering the sealig of large surfaces by gaskets very dilfh cult. It is not practical to exhaust the gases and vapors Within the vessel into the air; be cause these gases and vapors contain valuable matter and because they mnv he required subsequently, for carrying out the desired reaction,

In accordance with my invention there fore, 1 provide means for withdrawing gases end vapors from the vessel when the pressure becomes excessive end conserving these -ga ses end vapors forsuhseouent use. The

mater al to he treated, together with the desired amount of acid for producing the de sired reaction 18 charged into the vessel 2,

which is then sealed and heated to raise the temperature of the'contents, Connected to the vessei are one orniore excess vapor churnbers, in. the present instance there being three chambers 3, 4 and 5, connected together in series. The connection between the first chamber 3 and the vessel 2 is controlled by the valve 6 and the connections between the successive chambers are controlled, by the valves 7 and 8. The chambers may be of any desired size or shape and preferably lined with acid proofhriclr 9, so that they will not he deleteriously afiected by the acid vapor. Instead of being connected together,

vapor produced is large and the pressures produced ere'high, it is advantageous tov employ a plurality of small chambers rather than one large chamber, since the total pres sure on the wells of the large chamber would he very great.

lin carrying out the process, the veswl or its contents are heated, producing at pressure therein and when this pressure reaches: e predetermined value, the valve 6 is opened to permit some of the vapors to discharge into the chamber 3, thereby relieviug-the pressure Within the vessel. Should this relief not be sufficient to prevent the suhsequeflt formation of vepor reselling an excessive temperature, the valve? is opened, placing chamber 4 in communication with This operation is repeated as long as the pressure within the vessel tends to increase over the yn'edetermined value. When the temperature of reaction is reached, and reaction occurs, the vapors in the vessel are absorbed by the material, reducing the pressure in the vessel, and when this occurs, one or more of the valves ma heopei ed to. permit the vapors to flow back into the vessel, to maintain a pressure therein, and if necessary. to supply suflicient vapor to complete the reaction. Should there be an excess of vapor over that necessary to complete the reaction, it is retained in the chambers and introduced Ito the vessel after the next charge of man rial has been entered therein. The vapors are maintained in the vapor chambers and are not condensed therein, the

brick linings t) possessing sufiicient heat insulating properties to prevent condensation.

Prior to the use of the excess vapor chambers. it was necessary to employ concentrated acid in small quantities. or only in su'liicient quantity to react with the materiah without any appreciable excess. in order that prohibitive pressures would not be developed within the vessel. ll the use of this invention, an excess of acid may be used, since it is not lost and does not produce prohibitive pressures and a dilute acid may be used.

The dilute acid is desirable in the process because the water vapor is one of the great.- estca-talytic and chemical agents known and is further desirable on account of its lower cost.

I claim: g

1. A digesting apparatus" comprising a closed vessel in whichmaterial' is adapted to be heated to produce hot vapors under pressure, a closed heat insulated chamber connected to the vessel in which excess vapors may be stored and means for controlling the flow of vapors between the chamber and vessel.

2. A digesting apparatus comprising a closed vessel in which material is adapted to be heated to produce hot vapors under pressure. a plurality of closed heat insulated chambers connected in series and connected to the vessel in which excess vapors may be stored and means for controlling the flow ot' vapors between the chambers and the vessel.

In testimony ivhereof, I have hereunto set. my hand at an Francisco, California, this 17th day of June. 1918.

HARRY D. RANKIN In presence-of H. G. Pnos'n. 

